Here you’ll find 44 Diseases that start with A, organized from “Acne vulgaris” to “Autosomal dominant polycystic kidney disease”. The list includes common, high-impact and clinically significant conditions useful for quick lookups and deeper research. Entries include clinician-review notes, an internal A–Z index and source links for deeper reading.
Diseases that start with A are medical conditions whose accepted names begin with the letter A. Many, like “Acne vulgaris”, have long cultural recognition and broad public awareness.
Below you’ll find the table with Disease, Symptoms, Causes, Treatments, Notes and Sources.
Disease: The official condition name, standardized for lookup; you use it to find definitions, synonyms and related entries.
Symptoms: Key signs and symptoms (2–4 items) that help you quickly recognize or clinically differentiate the condition.
Causes: Primary causes and top risk factors summarized so you understand what drives the disease and who is at risk.
Treatments: First-line and typical treatment options, including common medications or procedures, and when to seek specialist referral.
Notes: Concise context such as prognosis, prevention tips, or testing cues that help you interpret the entry quickly.
Sources: Links to authoritative references and guidelines so you can follow up with reliable clinical or academic information.
Diseases that start with A
| Disease | ICD-10/ICD-11 code(s) | Common age / prevalence | Key symptoms (2–4) |
|---|---|---|---|
| Acne vulgaris | L70 | Teens, very common | Pimples, blackheads, oily skin, scarring |
| Alzheimer disease | G30 | Older adults, common (>65) | Memory loss, confusion, personality change |
| Asthma | J45 | Children & adults, common | Wheezing, shortness of breath, cough |
| Anemia | D50–D64 | All ages, common worldwide | Fatigue, pallor, shortness of breath |
| Appendicitis | K35–K37 | Children & young adults, common emergency | Abdominal pain (RLQ), nausea, fever |
| Atrial fibrillation | I48 | Older adults, common | Palpitations, breathlessness, dizziness |
| Autism spectrum disorder | F84.0 | Children, ~1 in 36 | Delayed speech, social communication difficulties, repetitive behaviors |
| Amyotrophic lateral sclerosis | G12.2 | Adults, rare (middle‑late age) | Progressive weakness, muscle wasting, speech difficulty |
| Atherosclerosis | I70 | Middle‑aged & older adults, common | Chest pain, claudication, often asymptomatic |
| Acute lymphoblastic leukemia | C91.0 | Children most affected, common childhood cancer | Fatigue, fever, bruising, bone pain |
| Acute myeloid leukemia | C92.0 | Adults, uncommon | Fatigue, infections, bleeding |
| Alcohol use disorder | F10 | Adults, common | Craving, loss of control, withdrawal symptoms |
| Anorexia nervosa | F50.0 | Adolescents/young adults, less common | Extreme weight loss, food restriction, fear of weight gain |
| Angina pectoris | I20 | Middle‑aged & older adults, common | Chest pressure, shortness of breath, exertional pain |
| Ankylosing spondylitis | M45 | Young adults, uncommon | Back pain, stiffness (worse morning), reduced spine mobility |
| Anxiety disorder | F41 | Adolescents & adults, very common | Excessive worry, restlessness, sleep disturbance |
| Aortic aneurysm | I71 | Older adults, men more common | Often asymptomatic, back/chest pain if expanding |
| Aortic stenosis | I35 | Older adults, common | Exertional breathlessness, chest pain, fainting |
| Amyloidosis | E85 | Adults, rare | Fatigue, swelling, neuropathy, organ dysfunction |
| Addison disease | E27.1 | Adults, uncommon | Fatigue, weight loss, low blood pressure, hyperpigmentation |
| Age‑related macular degeneration | H35.3 | Older adults, common | Central vision loss, blurred writing, distortion |
| Atopic dermatitis | L20 | Children & adults, common | Itchy, red, scaly patches, rash |
| Alopecia areata | L63 | Children & adults, uncommon | Sudden patchy hair loss, smooth bald areas |
| Alcoholic liver disease | K70 | Adults who drink heavily, common | Fatigue, jaundice, abdominal pain |
| Acute pancreatitis | K85 | Adults, common cause of hospital admission | Severe abdominal pain, nausea, vomiting, high enzymes |
| Autoimmune hepatitis | K75.4 | Adults, uncommon | Fatigue, jaundice, abdominal discomfort, elevated liver tests |
| Aplastic anemia | D61 | All ages, rare | Fatigue, infections, bleeding |
| Acute coronary syndrome | I20.0–I21 | Adults, common emergency | Chest pain, sweating, nausea, breathlessness |
| Actinic keratosis | L57.0 | Older adults, common with sun exposure | Rough scaly patches on sun‑exposed skin |
| Allergic rhinitis | J30 | Children & adults, very common | Sneezing, nasal congestion, itchy eyes |
| Acute otitis media | H66 | Children, very common | Ear pain, fever, hearing loss |
| Acute kidney injury | N17 | All ages, common in hospitalized patients | Reduced urine output, swelling, confusion, high creatinine |
| Antiphospholipid syndrome | D68.6 | Adults, uncommon | Recurrent clots, pregnancy loss |
| Actinomycosis | A42 | Adults, rare | Chronic draining sinus, firm mass, fever |
| Anthrax | A22 | Rare, occupational/bioterrorism cases | Skin ulcers (black), fever, severe respiratory distress |
| Aspergillosis | B44 | Immunocompromised & lung disease patients, uncommon | Cough, breathlessness, fever, hemoptysis |
| Adenovirus infection | B97.0 | Children, common | Fever, conjunctivitis, sore throat, cough |
| Acromegaly | E22.0 | Adults (middle age), rare | Enlarged hands/feet, facial changes, headache |
| Arthritis | M13 | Adults, very common | Joint pain, stiffness, swelling |
| Aortic dissection | I71.0 | Middle‑aged & older adults, rare emergency | Sudden severe chest/back pain, pulse deficits |
| Amebiasis | A06 | Areas with poor sanitation, variable | Diarrhea, abdominal pain, bloody stools |
| Acute rheumatic fever | I00 | Children & adolescents in some regions, uncommon | Fever, joint pain, heart murmur, rash |
| Angioedema | T78.3 | All ages, variable (allergic/genetic) | Rapid swelling of face, lips, airway, hives |
| Autosomal dominant polycystic kidney disease | Q61.3 | Adults (familial), 1 in ~1,000 | High blood pressure, abdominal pain, kidney cysts |
Descriptions
Acne vulgaris
Blocked hair follicles from excess oil and bacteria; topical retinoids, benzoyl peroxide or oral antibiotics; dermatologist for severe scarring.
Alzheimer disease
Progressive brain degeneration causing memory and thinking decline; age and genetics are risks; cholinesterase inhibitors, supportive care, refer to neurology.
Asthma
Chronic airway inflammation often triggered by allergies or pollution; inhaled bronchodilators and steroids; see respiratory specialist if uncontrolled.
Anemia
Low red blood cells/hemoglobin from iron deficiency, chronic disease or genetics; treat cause, iron supplements or transfusion when needed.
Appendicitis
Inflamed appendix usually from blockage/infection; requires urgent surgery (appendectomy) and antibiotics; emergency referral.
Atrial fibrillation
Irregular fast heart rhythm increasing stroke risk; rate/rhythm control and anticoagulation; cardiology referral often needed.
Autism spectrum disorder
Neurodevelopmental condition with genetic and environmental factors; early behavioral therapies, educational supports, multi‑disciplinary care.
Amyotrophic lateral sclerosis
Motor neuron degeneration causing progressive paralysis; no cure, riluzole/edavarone may slow decline; neurology referral essential.
Atherosclerosis
Plaque buildup in arteries from cholesterol, smoking, hypertension; lifestyle, statins, blood pressure control; vascular specialist for complications.
Acute lymphoblastic leukemia
Malignant proliferation of lymphoid precursors; chemotherapy is mainstay, sometimes stem cell transplant; hematology/oncology care required.
Acute myeloid leukemia
Malignancy of myeloid precursors causing marrow failure; chemotherapy and targeted agents, possible transplant; urgent hematology referral.
Alcohol use disorder
Problematic alcohol use from genetic and social factors; brief intervention, counseling, disulfiram/naltrexone, addiction services referral.
Anorexia nervosa
Eating disorder with high medical risk; psychiatric therapy, nutritional rehab, medical monitoring and specialist care.
Angina pectoris
Ischemic chest pain from coronary artery disease; nitrates, beta‑blockers, statins, cardiology evaluation for testing/revascularization.
Ankylosing spondylitis
Autoimmune inflammatory disease affecting spine; NSAIDs, physiotherapy, TNF inhibitors; rheumatology referral advised.
Anxiety disorder
Excessive or persistent anxiety from biological and psychological factors; CBT and SSRI/SNRI medications; mental health referral if severe.
Aortic aneurysm
Abnormal aortic dilation from atherosclerosis or genetics; blood pressure control, surveillance, surgical repair if large; vascular surgery referral.
Aortic stenosis
Narrowing of aortic valve usually from calcification; valve replacement for severe cases; cardiology/cardiothoracic referral.
Amyloidosis
Protein misfolding and tissue deposition—primary or secondary forms; treat underlying cause; specialist hematology or nephrology input often needed.
Addison disease
Primary adrenal insufficiency usually autoimmune; replace cortisol and aldosterone, endocrinology referral.
Age‑related macular degeneration
Degeneration of central retina; smoking is a risk; anti‑VEGF injections for wet form, ophthalmology care.
Atopic dermatitis
Chronic inflammatory skin disease linked to allergies; emollients, topical steroids, antihistamines; dermatology referral if severe.
Alopecia areata
Autoimmune attack on hair follicles; steroid injections, topical immunotherapy; dermatology care recommended.
Alcoholic liver disease
Liver inflammation and scarring from chronic alcohol use; abstinence, nutritional support, hepatology referral for cirrhosis.
Acute pancreatitis
Inflammation usually from gallstones or alcohol; fasting, IV fluids, pain control; gastroenterology/surgical input if severe.
Autoimmune hepatitis
Immune‑mediated liver inflammation; steroids and azathioprine, hepatology referral.
Aplastic anemia
Bone marrow failure causing pancytopenia—often idiopathic or drug‑related; immunosuppression or bone marrow transplant; hematology referral.
Acute coronary syndrome
Spectrum from unstable angina to myocardial infarction due to coronary blockage; urgent revascularization, antiplatelet therapy; emergency cardiology.
Actinic keratosis
Pre‑cancerous skin lesions from UV damage; cryotherapy, topical treatments, dermatology evaluation.
Allergic rhinitis
Immune reaction to allergens; nasal steroids, antihistamines, allergen avoidance or immunotherapy; ENT/allergy referral if persistent.
Acute otitis media
Middle ear infection often after viral URTI; analgesics, watchful waiting or antibiotics; pediatrician or ENT if recurrent.
Acute kidney injury
Rapid loss of kidney function from dehydration, toxins or ischemia; treat cause, IV fluids, nephrology when severe.
Antiphospholipid syndrome
Autoimmune hypercoagulable disorder causing blood clots; long‑term anticoagulation and specialist rheumatology/hematology care.
Actinomycosis
Bacterial infection (Actinomyces) causing chronic abscesses; long‑term antibiotics and sometimes surgery, infectious disease referral.
Anthrax
Infection by Bacillus anthracis; antibiotics and antitoxin, public health and infectious disease emergency management.
Aspergillosis
Fungal infection from Aspergillus species; antifungals and surgery for invasive disease, infectious disease referral.
Adenovirus infection
Viral respiratory and GI infections common in children; supportive care, rarely severe—pediatrics/infectious disease for complications.
Acromegaly
Excess growth hormone usually from pituitary tumor; surgery, somatostatin analogues, endocrinology care.
Arthritis
Joint inflammation from osteoarthritis, autoimmune or infection; analgesics, physiotherapy, rheumatology if inflammatory.
Aortic dissection
Tear in aortic wall often from hypertension or connective tissue disease; urgent imaging and surgical/endovascular repair.
Amebiasis
Parasitic intestinal infection (Entamoeba histolytica); metronidazole or tinidazole and follow‑up, travel medicine/infectious disease advice.
Acute rheumatic fever
Immune reaction after strep throat causing heart and joint inflammation; antibiotics and anti‑inflammatories, cardiology/rheumatology follow‑up.
Angioedema
Allergic or bradykinin‑mediated swelling; epinephrine for allergic reactions, C1 inhibitor for hereditary forms, emergency care if airway threatened.
Autosomal dominant polycystic kidney disease
Genetic disorder with progressive renal cysts leading to kidney failure; blood pressure control, nephrology care and transplant when needed.